Fan



Dec. 8, 1936. M. s. LEONARD 2,063,174

FAN

Filed Sept. 18, 1955.

Patented Dec. 1936 UNITED STATES PATENT OFF-ICE FAN Application September 18, 1935, Serial No. 41,037

3 Claims.

The principal object of the present invention is to provide a simple and inexpensive mechanism for effectively operating the vanes without cramping or binding.

With this and other objects in view, as will hereinafter appear, the present invention comprises the fan and vane operating mechanism hereinafter described and particularly defined in the claims.

In the accompanying drawing, Fig. 1 is an end view of a forced draft fan embodying the features of the present invention; Fig. 2 is a section on line 22 of Fig. 1; Fig. 3 is a section on line 3-4 of Fig. 2; Fig. 4 is a section on 'line 4-4 of Fig. 2; and Fig.v 5 is an enlarged detail view of the hub and rotary control member.

The fan illustrated in the drawing comprises a casing 6 having a converging inlet'8. The fan has a shaft l0 on which is mounted a wheel or rotor of any suitable form.

Surrounding the shaft and-free thereof is a huh I! having an outer cylindrical portion acting as I a journal for the rotary control member to be subsequently described, and atits inner end a conical portion 14 opposed to the inlet wall. Attached between the portion I4 of the hub and the wall 8 is a series of rods 16. The rods are threaded at their inner ends into the hub and are supported on the inlet at their outer ends between nuts 18. The rods form the support for the hub and also serve as pivots for the adjustable vanes. The rods are normal to the surface of the inlet wall and are therefore inclined to the axis of the shaft, as shown in Fig. 2.

The vanes are indicated at 20, each comprising a piece of flat sheet metal having a semi-circular groove 22 half surrounding the pivot It. At the bottom, each vane is welded to a crank plate 24 having a semi-circular opening opposed to the groove 22. The top of each vane is cut away, as indicated at 26, and a collar 28 aligning with the groove 22 is welded to the vane. The same cut-away portion also accommodates one of the nuts l8. The vanes are therefore supported on the pivot rods at top and bottom by the collar 28 and the plate 24 and as shown in Figs. 3 and 4, the fit is loose enough to permit free movement of each vane on its pivot.

equal in number to the vanes.

Journaled on the cylindrical portion of the hub 12 is a rotary control member 30 which is shown in Fig. 5. The control member has a conical portion 32 formed with longitudinal grooves 34 A follower 36 is attached to the plate 24 and extends into one of the grooves 34. Upon rotation of the control member 30, the plates 24 are rocked to move all of the vanes 2|! simultaneously and uniformly to their adjusted positions.

The control member 30 is adjusted by means of a rod 38 connected by links with a rod 42 connected to a bell crank 44 attached to the casing. The rod 38 is threaded into the control member and, as shown in Fig. 5, has a smooth end 46 received in an annular groove 48 of the hub. A retaining bolt 50 which is threaded into the control member also has an end projecting into the groove 48 whereby the control member is maintained in proper axial position on the hub while permitting free rotation of the control member. The vanes may be both operated either manually or automatically by any suitable mechanism connected with the bell crank 44.

According to the present invention, a uniform rotary movement may be imparted to the several vanes throughout the whole range from wide open to substantially closed position, and without cramping or binding of the parts. The construction is simple and inexpensive, and is applicable to fans of any size.

The invention having been thus described, what is claimed is:

1. A fan having a shaft, a converging inlet, a hub surrounding the shaft, pivot rods secured to the hub and inlet and supporting the hub from the inlet, the rods being perpendicular to the inlet wall, a plurality of vanes, one for each pivot rod, each vane having bearings through which the pivot rod passes, a rotary member journaled on the hub and having longitudinally extending grooves and a follower attached to each vane and engaging in a groove of the rotary member to adjust all the vanes simultaneously.

2. A fan having a shaft,- a converging inlet, a hub surrounding the shaft, pivot rods secured to the hub and inlet and supporting the hub from the inlet, the rods being perpendicular to the inlet wall, a plurality of vanes, one pivoted on each pivot rod, the hub having a cylindrical portion and a conical portion to receive the rods, a rotary member journaled on .the cylindrical portion of the hub and having a conical surface provided with longitudinal grooves, and a follower secured to the inner end of each vane to be received in a groove of the rotary member.

3. A fan having a shaft, aconverging inlet, a hub surrounding the shaft, pivot rods secured to the hub and inlet and supporting the hub from the'inlet, the rods being perpendicular to the inlet wall, vanes rotatable on the pivot rods, a rotary actuating member journalled on the hub and having longitudinally extending grooves, and a. crank attached to the inner .end of each vane, the cranks having followers received in the grooves of the rotary actuating member to adjust all the vanes simultaneously.

' MERTON s. LEONARD.- 

